Method and system for providing data communication in continuous glucose monitoring and management system

ABSTRACT

Method and system for providing data monitoring and management including RF communication link over which a transmitter and a receiver is configured to communicate, the transmitter configured to periodically transmit a data packet associated with a detected analyte level received from an analyte sensor, and the receiver configured to identify the transmitter as the correct transmitter for which it is configured to receive the data packets, and to continue to receive the data packets from the transmitter once the transmitter identification has been verified, is provided.

RELATED APPLICATIONS

The present application is a Continuation-in-Part of and claims priorityunder 35 USC §120 to U.S. patent application Ser. No. 10/745,878 filedDec. 26, 2003, now U.S. Pat. No. 7,811,231 entitled “Continuous GlucoseMonitoring System and Methods of Use,” the disclosure of which isincorporated herein by reference for all purposes and which claimspriority under 35 USC §119 to Provisional Patent Application No.60/437,374 filed Dec. 31, 2002.

The present application also claims priority under 35 USC §119 toProvisional Patent Application No. 60/545,362 filed Feb. 17, 2004,entitled “RF Link Protocol For Data Communication Systems,” thedisclosure of which is incorporated herein by reference for allpurposes.

BACKGROUND

The present invention relates to an in-vivo continuous glucosemonitoring and management system. More specifically, the presentinvention relates to communication protocol for data communicationbetween, for example, a transmitter and a receiver, in the continuousglucose monitoring and management systems for insulin therapy.

In data communication systems such as continuous glucose monitoringsystems for insulin therapy, analyte levels such as glucose levels of apatient are continuously monitored and the measured glucose levels areused for diabetes treatment. For example, real time values of measuredglucose levels would allow for a more robust and accurate diabetestreatment. Indeed, accurately measured glucose levels of a diabeticpatient would enable a more effective insulin therapy by way of moretimely bolus determination and administration.

In such data monitoring systems, it is important for the measuredglucose levels or data to be effective and less error prone in datatransmission and/or manipulation. Indeed, it would be desirable to havea continuous glucose monitoring and management system that provides arobust and substantially error free data communication between thecomponents or electronic devices in the system. More specifically, itwould be desirable to have a reliable communication protocol between thetransmitter and the receiver in a continuous glucose monitoring andmanagement system that allows for substantially real time datacommunication between the transmitter and the receiver for communicatingdata signals associated with the components such as componentidentification information as well as measured glucose values.

SUMMARY OF THE INVENTION

In accordance with the various embodiments of the present invention,there is provided method and system for providing RF communicationprotocol between one or more signal transmission devices and one or morecorresponding signal reception devices in a data monitoring andmanagement system such as continuous glucose monitoring systems.

In one embodiment, there is provided an RF communication link, atransmitter coupled to the communication link where the transmitterperiodically transmits a data packet at a given time interval over thecommunication link to a receiver that receives a first transmitted datapacket, and once the transmitter identification has been verified, thereceiver continues receiving subsequent data packets from thetransmitter.

In one embodiment, the receiver may be configured to verify thetransmitter identification based on the transmitter identificationinformation encoded with the first transmitted data packet.

In a further embodiment, a medication delivery unit such as an insulinpump may be provided and that is configured to communicate with thereceiver to receive detected glucose level of a patient. In such a case,the transmitter may be configured to be in signal communication with ananalyte sensor such as a blood glucose sensor that repeatedly measuresblood glucose level of a patient at a predetermined time interval andtransmits that information to the transmitter subsequent transmission,over the RF communication link, to the receiver. The receiver/monitormay be configured to display the measured glucose level informationincluding, for example, trend information, as well as to perform otherfunctions such as bolus and/or basal rate modification determinations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a continuous glucose monitoring and management systemin accordance with one embodiment of the present invention;

FIG. 2 is a block diagram of the transmitter of the system shown in FIG.1 in accordance with one embodiment of the present invention;

FIG. 3 is a block diagram of the receiver of the system shown in FIG. 1in accordance with one embodiment of the present invention;

FIG. 4 is an illustration of the application data including the sensordata from the transmitter of the system shown in FIG. 1 in accordancewith one embodiment of the present invention;

FIGS. 5A-5C illustrate a data packet table for Reed-Solomon encoding inthe transmitter, a depadded data table, and a data packet transmittedfrom the transmitter, respectively, in accordance with one embodiment ofthe system of FIG. 1;

FIG. 6 illustrates the data packet transmit window and time slots fortransmission from the transmitter in one embodiment of the presentinvention;

FIG. 7 illustrates the timing of the transmitted data packettransmission by the transmitter and reception by the receiver in oneembodiment of the present invention;

FIG. 8 illustrate data packet at the receiver for demodulation inaccordance with one embodiment of the present invention; and

FIG. 9 is a flowchart illustrating the transmitter-receivercommunication of the system shown in FIG. 1 in accordance with oneembodiment of the present invention.

DETAILED DESCRIPTION

FIG. 1 illustrates a continuous glucose monitoring and management system100 in accordance with one embodiment of the present invention. In suchembodiment, the continuous glucose monitoring and management system 100includes a sensor unit 101, a transmitter unit 102 coupled to the sensorunit 101, and a receiver unit 104 which is configured to communicatewith the transmitter 102 via a communication link 103. The receiver 104may be further configured to transmit data to a data processing terminal105 for evaluating the data received by the receiver 104. Referringagain to the Figure, also shown in FIG. 1 is a medication delivery unit106 which is operatively coupled to the receiver 104. In one embodiment,the medication delivery unit 106 may be configured to administer apredetermined or calculated insulin dosage based on the informationreceived from the receiver 104. For example, as discussed in furtherdetail below, the medication delivery unit 106 in one embodiment mayinclude an infusion pump configured to administer basal profiles todiabetic patients, as well as to determine and/or administer one or moresuitable boluses for the diabetic patients.

Only one sensor 101, transmitter 102, communication link 103, receiver104, and data processing terminal 105 are shown in the embodiment of thecontinuous glucose monitoring and management system 100 illustrated inFIG. 1. However, it will be appreciated by one of ordinary skill in theart that the continuous glucose monitoring and management system 100 mayinclude one or more sensor 101, transmitter 102, communication link 103,receiver 104, and data processing terminal 105, where each receiver 104is uniquely synchronized with a respective transmitter 102.

In one embodiment of the present invention, the sensor 101 is physicallypositioned on the body of a user whose glucose level is being monitored.The term user as used herein is intended to include humans, animals, aswell as any other who might benefit from the use of the glucosemonitoring and management system 100. The sensor 101 maybe configured tocontinuously sample the glucose level of the user and convert thesampled glucose level into a corresponding data signal for transmissionby the transmitter 102. In one embodiment, the transmitter 102 ismounted on the sensor 101 so that both devices are positioned on theuser's body. The transmitter 102 performs data processing such asfiltering and encoding on data signals, each of which corresponds to asampled glucose level of the user, for transmission to the receiver 104via the communication link 103.

In one embodiment, the continuous glucose monitoring and managementsystem 100 is configured as a one-way RF communication path from thetransmitter 102 to the receiver 104. In such embodiment, the transmitter102 is configured to continuously and repeatedly transmit the sampleddata signals received from the sensor 101 to the receiver 104, withoutacknowledgement from the receiver 104 that the transmitted sampled datasignals have been received. For example, the transmitter 102 may beconfigured to transmit the encoded sampled data signals at a fixed rate(e.g., at one minute intervals) after the completion of the initialpower on procedure. Likewise, the receiver 104 may be configured todetect such transmitted encoded sampled data signals at predeterminedtime intervals. While a uni-directional communication path from thetransmitter 102 to the receiver 104 is described herein, within thescope of the present invention, a bi-directional communication betweenthe transmitter 102 and the receiver 104 is also included. Indeed, thetransmitter 102 may include a transceiver to enable both datatransmission and reception to and from the receiver 104 and/or any otherdevices communicating over the communication link 103 in the continuousdata monitoring and management system 100.

As discussed in further detail below, in one embodiment of the presentinvention the receiver 104 includes two sections. The first section isan analog interface section that is configured to communicate with thetransmitter 102 via the communication link 103. In one embodiment, theanalog interface section may include an RF receiver and an antenna forreceiving and amplifying the data signals from the transmitter 102,which are thereafter demodulated with a local oscillator and filteredthrough a band-pass filter. The second section of the receiver 104 is adata processing section which is configured to process the data signalsreceived from the transmitter 102 such as by performing data decoding,error detection and correction, data clock generation, and data bitrecovery.

In operation, upon completing the power-on procedure, the receiver 104is configured to detect the presence of the transmitter 102 within itsrange based on the strength of the detected data signals received fromthe transmitter 102. For example, in one embodiment, the receiver 104 isconfigured to detect signals whose strength exceeds a predeterminedlevel to identify the transmitter 102 from which the receiver 104 is toreceive data. Alternatively, the receiver 104 in a further embodimentmay be configured to respond to signal transmission for a predeterminedtransmitter identification information of a particular transmitter 102such that, rather than detecting the signal strength of a transmitter102 to identify the transmitter, the receiver 104 may be configured todetect transmitted signal from a predetermined transmitter 102 based onthe transmitted transmitter identification information corresponding tothe pre-assigned transmitter identification information for theparticular receiver 104.

In one embodiment, the identification information of the transmitter 102includes a 16-bit ID number. In an alternate embodiment, the ID numbermay be a predetermined length including a 24-bit ID number or a 32-bitID number. Further, any other length ID number may also be used. Thus,in the presence of multiple transmitters 102, the receiver 104 will onlyrecognize the transmitter 102 which corresponds to the stored orreconstructed transmitter identification information. Data signalstransmitted from the other transmitters within the range of the receiver104 are considered invalid signals.

Referring again to FIG. 1, where the receiver 104 determines thecorresponding transmitter 102 based on the signal strength of thetransmitter 102, when the receiver 104 is initially powered-on, thereceiver 104 is configured to continuously sample the signal strength ofthe data signals received from the transmitters within its range. If thesignal strength of the data signals meets or exceeds the signal strengththreshold level and the transmission duration threshold level, thereceiver 104 returns a positive indication for the transmitter 102transmitting the data signals. That is, in one embodiment, the receiver104 is configured to positively identify the transmitter 102 after onedata signal transmission. Thereafter, the receiver 104 is configured todetect positive indications for two consecutive data signaltransmissions for a predetermined time period. At such point, afterthree consecutive transmissions, the transmitter 102 is fullysynchronized with the receiver 104.

Upon identifying the appropriate transmitter 102, the receiver 104begins a decoding procedure to decode the received data signals. In oneembodiment, a sampling clock signal may be obtained from the preambleportion of the received data signals. The decoded data signals, whichinclude fixed length data fields, are then sampled with the samplingclock signal. In one embodiment of the present invention, based on thereceived data signals and the time interval between each of the threedata signal transmissions, the receiver 104 determines the wait timeperiod for receiving the next transmission from the identified andsynchronized transmitter 102. Upon successful synchronization, thereceiver 104 begins receiving from the transmitter 102 data signalscorresponding to the user's detected glucose level. As described infurther detail below, the receiver 104 in one embodiment is configuredto perform synchronized time hopping with the corresponding synchronizedtransmitter 102 via the communication link 103 to obtain the user'sdetected glucose level.

Referring yet again to FIG. 1, the data processing terminal 105 mayinclude a personal computer, a portable computer such as a laptop or ahandheld device (e.g., personal digital assistants (PDAs)), and thelike, each of which is configured for data communication with thereceiver via a wired or a wireless connection. Additionally, the dataprocessing terminal 105 may further be connected to a data network (notshown) for storing, retrieving and updating data corresponding to thedetected glucose level of the user.

FIG. 2 is a block diagram of the transmitter 102 of the continuousglucose monitoring and management system 100 in accordance with oneembodiment of the present invention. The transmitter 102 includes ananalog interface 201 configured to communicate with the sensor 101 (FIG.1), a user input 202, and a temperature detection section 203, each ofwhich is operatively coupled to a transmitter processing unit 204 suchas a central processing unit (CPU). Further shown in FIG. 2 are atransmitter serial communication section 205 and an RF transmitter 206,each of which is also operatively coupled to the transmitter processingunit 204. Moreover, a power supply 207 is also provided in thetransmitter 102 to provide the necessary power for the transmitter 102.Additionally, as can be seen from the Figure, clock 208 is provided to,among others, supply real time information to the transmitter processingunit 204.

In one embodiment, a unidirectional input path is established from thesensor 101 (FIG. 1) and/or manufacturing and testing equipment to theanalog interface 201, while a unidirectional output is established fromthe output of the RF transmitter 206. In this manner, a data path isshown in FIG. 2 between the aforementioned unidirectional input andoutput via a dedicated link 209 from the analog interface 201 to serialcommunication section 205, thereafter to the processing unit 204, andthen to the RF transmitter 206. As such, in one embodiment, through thedata path described above, the transmitter 102 is configured to transmitto the receiver 104 (FIG. 1), via the communication link 103 (FIG. 1),processed and encoded data signals received from the sensor 101 (FIG.1). Additionally, the unidirectional communication data path between theanalog interface 201 and the RF transmitter 206 discussed above allowsfor the configuration of the transmitter 102 for operation uponcompletion of the manufacturing process as well as for directcommunication for diagnostic and testing purposes.

Referring back to FIG. 2, the user input 202 includes a disable devicethat allows the operation of the transmitter 102 to be temporarilydisabled, such as, by the user wearing the transmitter 102. In analternate embodiment, the disable device of the user input 202 may beconfigured to initiate the power-up procedure of the transmitter 102.

As discussed above, the transmitter processing unit 204 is configured totransmit control signals to the various sections of the transmitter 102during the operation of the transmitter 102. In one embodiment, thetransmitter processing unit 204 also includes a memory (not shown) forstoring data such as the identification information for the transmitter102, as well as the data signals received from the sensor 101. Thestored information may be retrieved and processed for transmission tothe receiver 104 under the control of the transmitter processing unit204. Furthermore, the power supply 207 may include a commerciallyavailable battery pack.

The physical configuration of the transmitter 102 is designed to besubstantially water resistant, so that it may be immersed in non-salinewater for a brief period of time without degradation in performance.Furthermore, in one embodiment, the transmitter 102 is designed so thatit is substantially compact and light-weight, not weighing more that apredetermined weight such as, for example, approximately 18 grams.Furthermore, the dimensions of the transmitter 102 in one embodimentincludes 52 mm in length, 30 mm in width and 12 mm in thickness. Suchsmall size and weight enable the user to easily carry the transmitter102.

The transmitter 102 is also configured such that the power supplysection 207 is capable of providing power to the transmitter for aminimum of three months of continuous operation after having been storedfor 18 months in a low-power (non-operating) mode. In one embodiment,this may be achieved by the transmitter processing unit 204 operating inlow power modes in the non-operating state, for example, drawing no morethan approximately 1 μA. Indeed, in one embodiment, the final stepduring the manufacturing process of the transmitter 102 places thetransmitter 102 in the lower power, non-operating state (i.e.,post-manufacture sleep mode). In this manner, the shelf life of thetransmitter 102 may be significantly improved.

Referring again to FIG. 2, the analog interface 201 of the transmitter102 in one embodiment includes a sensor interface (not shown) configuredto physically couple to the various sensor electrodes (such as, forexample, working electrode, reference electrode, counter electrode, (notshown)) of the sensor 101 (FIG. 1) of the monitoring system 100. Theanalog interface section 201 further includes a potentiostat circuit(not shown) which is configured to generate the Poise voltage determinedfrom the current signals received from the sensor electrodes. Inparticular, the Poise voltage is determined by setting the voltagedifference between the working electrode and the reference electrode(i.e., the offset voltage between the working electrode and thereference electrode of the sensor 102). Further, the potentiostatcircuit also includes a transimpedance amplifier for converting thecurrent signal on the working electrode into a corresponding voltagesignal proportional to the current. The signal from the potentiostatcircuit is then low pass filtered with a predetermined cut-off frequencyto provide anti-aliasing, and thereafter, passed through a gain stage toprovide sufficient gain to allow accurate signal resolution detectedfrom the sensor 101 for analog-to-digital conversion and encoding fortransmission to the receiver 104.

Referring yet again to FIG. 2, the temperature detection section 203 ofthe transmitter 102 is configured to monitor the temperature of the skinnear the sensor insertion site. The temperature reading is used toadjust the glucose readings obtained from the analog interface 201. Asdiscussed above, the input section 202 of the transmitter 102 includesthe disable device which allows the user to temporarily disable thetransmitter 102 such as for, example, to comply with the FAA regulationswhen aboard an aircraft. Moreover, in a further embodiment, the disabledevice may be further configured to interrupt the transmitter processingunit 204 of the transmitter 102 while in the low power, non-operatingmode to initiate operation thereof.

The RF transmitter 206 of the transmitter 102 may be configured foroperation in the frequency band of 315 MHz to 322 MHz, for example, inthe United States. Further, in one embodiment, the RF transmitter 206 isconfigured to modulate the carrier frequency by performing FrequencyShift Keying and Manchester encoding. In one embodiment, the datatransmission rate is 19,200 symbols per second, with a minimumtransmission range for communication with the receiver 104.

FIG. 3 is a block diagram of the receiver 104 of the continuous glucosemonitoring and management system 100 in accordance with one embodimentof the present invention. Referring to FIG. 3, the receiver 104 includesa blood glucose test strip interface 301, an RF receiver 302, an input303, a temperature detection section 304, and a clock 305, each of whichis operatively coupled to a receiver processing unit 307. As can befurther seen from the Figure, the receiver 104 also includes a powersupply 306 operatively coupled to a power conversion and monitoringsection 308. Further, the power conversion and monitoring section 308 isalso coupled to the receiver processing unit 307. Moreover, also shownare a receiver communication section 309, and an output 310, eachoperatively coupled to the receiver processing unit 307.

In one embodiment, the test strip interface 301 includes a glucose leveltesting portion to receive a manual insertion of a glucose testingstrip, and thereby determine and display the glucose level of thetesting strip on the output 310 of the receiver 104. This manual testingof glucose can be used to calibrate sensor 101. The RF receiver 302 isconfigured to communicate, via the communication link 103 (FIG. 1) withthe RF transmitter 206 of the transmitter 102, to receive encoded datasignals from the transmitter 102 for, among others, signal mixing,demodulation, and other data processing. The input 303 of the receiver104 is configured to allow the user to enter information into thereceiver 104 as needed. In one aspect, the input 303 may include one ormore keys of a keypad, a touch-sensitive screen, or a voice-activatedinput command unit. The temperature detection section 304 is configuredto provide temperature information of the receiver 104 to the receiverprocessing unit 307, while the clock 305 provides, among others, realtime information to the receiver processing unit 307.

Each of the various components of the receiver 104 shown in FIG. 3 arepowered by the power supply 306 which, in one embodiment, includes abattery. Furthermore, the power conversion and monitoring section 308 isconfigured to monitor the power usage by the various components in thereceiver 104 for effective power management and to alert the user, forexample, in the event of power usage which renders the receiver 104 insub-optimal operating conditions. An example of such sub-optimaloperating condition may include, for example, operating the vibrationoutput mode (as discussed below) for a period of time thus substantiallydraining the power supply 306 while the processing unit 307 (thus, thereceiver 104) is turned on. Moreover, the power conversion andmonitoring section 308 may additionally be configured to include areverse polarity protection circuit such as a field effect transistor(FET) configured as a battery activated switch.

The communication section 309 in the receiver 104 is configured toprovide a bi-directional communication path from the testing and/ormanufacturing equipment for, among others, initialization, testing, andconfiguration of the receiver 104. Serial communication section 309 canalso be used to upload data to a computer, such as time-stamped bloodglucose data. The communication link with an external device (not shown)can be made, for example, by cable, infrared (IR) or RF link. The output310 of the receiver 104 is configured to provide, among others, agraphical user interface (GUI) such as a liquid crystal display (LCD)for displaying information. Additionally, the output 310 may alsoinclude an integrated speaker for outputting audible signals as well asto provide vibration output as commonly found in handheld electronicdevices, such as mobile telephones presently available. In a furtherembodiment, the receiver 104 also includes an electro-luminescent lampconfigured to provide backlighting to the output 310 for output visualdisplay in dark ambient surroundings.

Referring back to FIG. 3, the receiver 104 in one embodiment may alsoinclude a storage section such as a programmable, non-volatile memorydevice as part of the processing unit 307, or provided separately in thereceiver 104, operatively coupled to the processing unit 307. Theprocessor 307 is further configured to perform Manchester decoding aswell as error detection and correction upon the encoded data signalsreceived from the transmitter 102 via the communication link 103.

FIG. 4 is an illustration of the application data including the sensordata from the transmitter of the system shown in FIG. 1 in accordancewith one embodiment of the present invention. Referring to FIG. 4, inone embodiment, each data packet from the transmitter 102 includes 15bytes as shown in the Figure. For example, the first byte (zero byte)corresponds to the transmitter 102 transmit time information (“TxTime”)which is a protocol value and is configured to start at zero andincremented with every data packet. In one embodiment, the transmit time(TxTime) data is used for synchronizing the transmit window hopping anderror correction as discussed in further detail below. Referring back toFIG. 4, the transmit data packet also includes bytes 1 to 14 whichcomprise the application payload that includes signal representation ofthe glucose values measured by the sensor 101, and which is to beencoded with transmission protocol information and transmitted to thereceiver 104. For example, in one embodiment, the transmission datapacket is Reed Solomon encoded and transmitted to the receiver 104,which is configured to detect and correct up to 3 symbol errors. Itshould be noted that the Reed Solomon encoding discussed herein may beconfigured to perform forward error correction encoding on thetransmission data packet prior to transmission to the receiver 104.

FIGS. 5A-5C illustrate a data packet table for Reed-Solomon encoding inthe transmitter, a depadded data table, and a data packet transmittedfrom the transmitter, respectively, of the continuous glucose monitoringand management system of FIG. 1 in accordance with one embodiment.Referring to FIG. 5A, it can be seen that the Reed Solomon encoded datablock contents include 15 bytes of packed data (FIG. 4), one byte of theleast significant bit (LSB) of the transmitter identificationinformation (TxID), one byte of the least middle significant bit of thetransmitter identification information (TxID), one byte of the mostmiddle significant bit of the transmitter identification information (TxID), one byte of the most significant bit (MSB) of the transmitteridentification information (TxID), 230 bytes of zero pads, 6 bytes ofparity symbols, to comprise a total of 255 bytes.

In one embodiment, the Reed Solomon encode procedure at the transmitter102 uses 8 bit symbols for a 255 symbol block to generate the 6 paritysymbols. The encoding procedure may include the encoding of thetransmitter identification information into the parity symbols. Thetransmitter 102 in one embodiment is configured to build the dataportion (15 bytes of packed data) of the data block shown in FIG. 5A(for example, using a virtual realization of the table). The transmitter102 is configured to remove the 230 bytes of zero pads, and the 4 bytesof transmitter identification information (TxID), resulting in the 21bytes of depadded data block including the 15 bytes of packed data andthe 6 bytes of parity symbols as shown in FIG. 5B.

In one embodiment, the transmitter identification information (Tx ID) isnot included in the transmitted data transmitted from the transmitter102 to the receiver 104. Rather, the receiver 104 may be configured todetermine the transmitter identification information (Tx ID) from thereceived data by using Reed Solomon decoding. More specifically, whendecoding the first data packet received from a transmitter 102, thereceiver 104 may be configured to set the value corresponding to thetransmitter identification information (TxID) to zero, and to indicateto the Reed Solomon decoder that the transmitter identificationinformation (TxID) is known to be incorrect. The Reed Solomon decodermay then be configured to use this information to more effectively“correct” during the error correction procedure, and therefore torecover the transmitter identification information (TxID) from thereceived data. Indeed, in subsequent data packets, the received pads andthe received data packet with the known transmitter identificationinformation (TxID) are used to facilitate with the error detection.

Referring back to FIG. 5C, a link prefix is added to the depadded datablock to complete the data packet for transmission to the receiver 104.The link prefix allows the receiver 104 to align the byte boundariesassociated the transmitted data from the transmitter 102 for ReedSolomon decoding as described in further detail below. Morespecifically, as shown in FIG. 5C, the transmitter 102 is configured toadd 4 bytes of link prefix (0x00, 0x00, 0x15, and 0x67) to the 21 bytesof depadded data block to result in 25 bytes of data packet. In thismanner, once powered up and enabled in operational mode, the transmitter102 is configured to transmit the 25 byte data packet once every minute.More specifically, in one embodiment, the transmitter 102 may beconfigured to Manchester encode the data at 2 Manchester bits per databit (0=10; 1=01), and transmit the Manchester bits at 20,000 Manchesterbits per second. It should be noted here that the Manchester encoding inone embodiment is configured to encode the data clock with thetransmitted data. Further, it may be configured to shift the frequencycontent up so that there is no DC (direct current) content. Thetransmitter 102 may be configured to transmit the data packets with themost significant bit—byte zero first.

In this manner, in one embodiment of the present invention, thetransmitter 102 may be configured to transmit a data packet once perminute, where the time between each data packet transmit may rangebetween 50 to 70 seconds. In one embodiment, the transmitter may beconfigured to maintain a minute tick reference to schedule transmitwindows as discussed in further detail below. The first data packet thenmay be scheduled relative to that time.

More specifically, the time that the data packet is transmitted by thetransmitter 102 may vary from minute to minute. For example, in oneembodiment, the first 10 seconds after a minute tick are divided intotime windows each being 25 milliseconds wide, and numbered from 0 to399. The transmitter 102 may then be configured to select the transmitwindow based upon a predetermined transmit configuration.

In one embodiment, the transmitter 102 may be configured to select totransmit window based on the transmitter identification information(TxID) and the transmit time information (TxTime). As discussed infurther detail below, the transmit time (TxTime) represents a value thatstarts at zero and increments to 256 for each data packet sent. When thetransmit time (TxTime) is equal to zero, a pseudo random numbergenerator is seeded with the transmitter identification information(TxID). Then, for each minute, the pseudo random number generator may beused to generate the transmit window for that minute.

FIG. 6 illustrates the data packet transmit window and time slots fortransmission from the transmitter in one embodiment of the presentinvention. In particular, the transmit window in one embodiment of thepresent invention may be configured such that 30 collocated transmittersmay operate without any one of them losing data due to transmittercollisions. As discussed in further detail below, to prevent two or moretransmitters from continuously colliding, a time hopping mechanism maybe implemented to randomize the transmit time.

For example, each minute may be divided into 25 millisecond windows asshown in FIG. 6. As shown in the Figure, a one second window may bedivided into 40 time slots, and further, a one minute window may besegmented into 2,400 time slots for transmission. With the transmitterconfigured to transmit on average once per minute, the data burst is 200bits long including preamble and a 1 millisecond transmitter warm up,resulting in approximately 25 millisecond burst duration.

Accordingly, in order to prevent transmission from two transmitters fromcontinuously colliding with each other, the transmit time may be offseton each transmission. In one embodiment, the transmit time offsetconfiguration may be implemented as a function of the transmissionidentification information (TxID) and the transmit time (TxTime).

For example, in one embodiment, with the transmission at once per minuteplus 10 seconds, during this 10 second period, 80 time segment windowsmay be reserved from sensor measurements. Thus since there are 40transmission windows per each second, the 10 second duration results in400 transmission windows from which the 80 time segment windows isdeducted (for sensor measurement). This results in 320 possibletransmission windows to select when to transmit the data packet by thetransmitter 102. In one embodiment, the transmit time (TxTime) may be 8bits, and each transmitter may be configured to select a time slot fromthe 320 possible transmission windows for data transmission. It shouldalso be noted here that once the receiver 104 corresponding to aparticular transmitter 102 is aware of the transmit time (TxTime)associated with the transmitter 102, the receiver 104 may determine thefuture transmit window times associated with the transmitter 102 withoutadditional information from the transmitter 102. This providessubstantial advantages, for example, from power savings perspective, inthat the receiver 104 may substantially accurately anticipate thetransmit window for data transmission from the transmitter 102, and thuscapture and receive substantially all of the transmitted data packetsfrom the transmitter 102 without continuously listening out for thetransmission data.

FIG. 7 illustrates the timing of the transmitted data packettransmission by the transmitter and reception by the receiver in oneembodiment of the present invention. Referring to the Figure, in oneembodiment, the receive window for the receiver 104 may be configured tobe synchronized with the corresponding transmitter when a startindicator of the transmission is detected by the receiver 104. Forexample, the receiver 104 may be configured to synchronize the receivewindow with the associated transmitter 102 accurately with a phaselocked start indicator. From the phase locked start indicator, thereceiver 104 may predict the subsequent transmit burst time, with theerror being limited to the relative drift between transmissions. When atransmit data packet is missed, the receiver 104 may be configured towiden the receive window. In one embodiment, the receive window may beconfigured relatively narrow so as to maintain the duty cycle low. Inthe case where the transmitter time drifts substantially to cause thereceiver to miss a transmission, the next receive window may beconfigured to open substantially relatively wide to ensure that the datapacket is not missed.

Referring back to the Figures, and each transmission time, thetransmitter 102 is configured to send a data packet which is Manchesterencoded, at two Manchester bits per data bit, with 1,900 Manchester bitsper second. More specifically, the transmit data packet received by thereceiver 104 in one embodiment comprises a dotting pattern, a data startindicator, and a forward error correction data as shown in FIG. 7. Inone embodiment, the receiver 104 may be configured to use the dottingpattern to phase lock to the received signal and to extract thetransmitted data clock information.

For optimal accuracy, in one embodiment, the received data should besampled in the middle of the bit time. The receiver 104 needs tomaintain phase lock to the data to limit the accumulation of timingerror. Referring again to FIG. 7, the start indicator is configured toprovide immunity to bit errors during data synchronization. Morespecifically, after determining the bit time and phase, the receiver 104is configured to start collecting and saving the received data bits. Thereceiver 104 may be configured to search the received bit stream fordata start indicator. In one embodiment, a 12-bit start indicator may beimmune to all 2 bit errors. In other words, the receiver 104 may beconfigured such that it does not false detect or miss the startindicator with up to 2 bit errors. In one embodiment, a 13 bit startindicator may be used.

Referring again to FIG. 7, the transmitter identification information(TxID) may in one embodiment be used to schedule transmit time. Asdiscussed above, the transmitter identification information (TxID) maybe included in the forward error correction parity determination, andnot transmitted with the transmission data packet.

Furthermore, the receiver 104 may be configured to discard a data packetwhen one of the following error conditions is detected. First, thereceiver 104 may be configured to discard the data packet where the ReedSolomon decoding procedure indicates that the data packet isuncorrectable. Second, after decoding, the receiver 104 may beconfigured to verify that all of the zero pad symbols are zero. Anon-zero indicates that the Reed Solomon decode procedure hasinadvertently “corrected” a pad byte from zero to some other value. Inthis case, the receiver 104 is configured to discard the associated datapacket.

Third, after decoding, the receiver 104 is configured to verify that thetransmitter identification information (TxID) pad symbols correspond tothe correct transmitter identification information (TxID). Again, anincorrect value representing the transmitter identification information(TxID) indicates that the Reed Solomon decode procedure hasinadvertently “corrected” a pad byte to some other value. In this case,as before, the receiver 104 is configured to discard the data packetassociated with the incorrect transmitter identification information(TxID). Finally, an unexpected value associated with the transmit time(TxTime) for the data packet will indicate an error, since the transmittime (TxTime) is a predictable and determinable value, and whichincrements for every packet transmitted, as discussed above. In thiscase, the receiver 104 is configured to discard the data packetassociated with the unexpected transmit time (TxTime) value.

Furthermore, in certain cases, the receiver 104 may be prevented fromreceiving the correct data from an in range transmitter 102. Theseinclude missed data synchronization, uncorrectable data packet due torandom noise, and uncorrectable data packet due to burst noise. Onaverage, at worst received signal strength, the receiver 104 may missone data packet every 1.7 days. Burst noise is a function of thephysical location, including the colliding of two transmitters that haveoverlapping transmission range. As discussed herein, the time hoppingprocedure makes it less likely that two transmitters will collideseveral times consecutively.

FIG. 8 illustrates data packet at the receiver for demodulation inaccordance with one embodiment of the present invention. As discussedabove, the receiver 104 in one embodiment may be configured todemodulate or extract the data clock from the received signal and tocapture the received bit stream. More specifically, during the receiver104 bit synchronization, the receiver 104 may be configured to establishphase lock during the leading zeros of the link prefix, to maintain thephase lock during the entire received bit stream, to save the datapacket contents with the most significant bit first, or to save the datapacket contents byte zero first.

With respect to receiver 104 frame synchronization, the receiver 104 inone embodiment may be configured to identify a bit sequence that is aHamming distance of 2 or less from the transmitted data start indicator(FIG. 7). Moreover, the receiver 104 may be configured so that thereceived bit stream is byte aligned using the first data bit as thefirst byte boundary.

In one embodiment, the receiver 104 may be configured to wait up to 70seconds for a data packet. The receiver 104 may be configured to performsynchronized time hopping with a corresponding transmitter 102, and tomaintain time hop synchronization for more than 30 minutes, for example,of un-received data packets. Alternatively, the receiver in oneembodiment may be configured to maintain time hop synchronization withthe relative temperature changes of the transmitter and receiver fromthe minimum and maximum crystal frequency extremes, which tests theability of the receiver 104 to track the transmitter 102 time base asthe crystal frequency of both devices changes with temperature.

Referring back to the Figures, the receiver 104 is configured to performReed Solomon decode procedure to the received data packet received fromthe transmitter 102. More specifically, the receiver 104 in oneembodiment is configured to build the Reed Solomon data block contentsas shown in FIG. 4 from the data packet received from the transmitter102. Again, the packed data are the first 15 bytes of the receivedpacket, and the parity symbols are the next 6 bytes. The zero pad bytesare set to zero.

Additionally, the receiver 104 may be configured to perform errordetection and corrections including determining whether the Reed Solomondecode function returns a success, whether all of the 230 zero pad bytesare still zero, where in each of the case, the receiver 104 isconfigured to discard the data packet if any of these checks fail.Moreover, in the case where the receiver 104 has acquired acorresponding transmitter 102, the receiver 104 may be configured tocheck that the 32 bit transmitter identification information (TxID) iscorrect, and also, whether the transmit window time (TxTime) value isaccurate (i.e., incrementing every minute). If any of these checks fail,the receiver 104 flags an error, and is configured to discard the datapacket associated with the error.

FIG. 9 is a flowchart illustrating the transmitter-receivercommunication of the system shown in FIG. 1 in accordance with oneembodiment of the present invention. Referring to FIG. 9, uponcompleting the power up procedure as discussed above, the receiver 104listens for the presence of a transmitter within the RF communicationlink range. When the transmitter 102 is detected within the RFcommunication link range at step 901, in one embodiment, the receiver104 may be configured to receive and store the identificationinformation corresponding to the detected transmitter 102.Alternatively, the receiver 102 may be pre-configured with thecorresponding transmitter identification information, and thus, will beconfigured to verify the transmitter identification based on the datatransmission received detected at step 901. More specifically, at step901, the receiver 104 may be configured to detect (or sample) datatransmission within its RF communication range. In one aspect, thereceiver 104 may be configured to identify a positive data transmissionupon ascertaining that the data transmission is above a predeterminedstrength level for a given period of time (for example, receiving threeseparate data signals above the predetermined strength level from thetransmitter 102 at one minute intervals over a period of five minutes).

At step 902, the receiver 104 is configured to determine whether thedetected signals within the RF communication range is transmitted fromthe transmitter 102 having the transmitter identification informationstored or reconstructed (e.g., regenerated) in the receiver 104. If itis determined at step 902 that the detected data transmission at step901 does not originate from the transmitter corresponding to thetransmitter identification information, then the procedure returns tostep 901 and awaits for the detection of the next data transmission.

On the other hand, if at step 902 it is determined that the detecteddata transmission is from the transmitter 102 corresponding to thetransmitter identification information, then at step 903, the receiverproceeds with decoding the received data and performing error correctionthereon. In one embodiment, the receiver is configured to performReed-Solomon decoding, where the transmitted data received by thereceiver is encoded with Reed-Solomon encoding. Furthermore, thereceiver is configured to perform forward error correction to minimizedata error due to, for example, external noise, and transmission noise.

Referring back to FIG. 9, after decoding and error correcting thereceived data, the receiver 104 at step 904 generates output datacorresponding to the decoded error corrected data received from thetransmitter 102, and thereafter, at step 905, the receiver 104 outputsthe generated output data for the user as a real time display of theoutput data, or alternatively, in response to the user operationrequesting the display of the output data. Additionally, beforedisplaying the output data for the user, other pre-processing proceduresmay be performed on the output data to for example, smooth out theoutput signals. In one aspect, the generated output data may include avisual graphical output displayed on the graphical user interface of thereceiver. Alternatively, the output data may be numerically displayedrepresenting the corresponding glucose level.

Referring to FIGS. 1 and 9, in one aspect of the present invention, thegenerated data output at step 905 may be provided to the medicationdelivery unit 106 (FIG. 1) to for analysis and therapy management, suchas bolus calculations and basal profile modifications to alter orotherwise adjust the level of insulin dosage administered to the patientvia the medication delivery unit 106 which may include an insulin pump.

Referring again to the Figures discussed above, the time hoppingprocedure of one embodiment is described. More specifically, since morethan one transmitter 102 may be within the receiving range of aparticular receiver 104, and each transmitting data every minute on thesame frequency, transmitter units 102 are configured to transmit datapackets at different times to avoid co-location collisions (that is,where one or more receivers 104 cannot discern the data signalstransmitted by their respective associated transmitter units 102 becausethey are transmitting at the same time).

In one aspect, transmitter 102 is configured to transmit once everyminute randomly in a window of time of plus or minus 5 seconds (i.e., ittime hops.) To conserve power, receiver 104 does not listen for itsassociated transmitter 102 during the entire 10 second receive window,but only at the predetermined time it knows the data packet will becoming from the corresponding transmitter 102. In one embodiment, the 10second window is divided into 400 different time segments of 25milliseconds each. With 80 time segments reserved for sensormeasurements as discussed above, there remain 320 time segments for thetransmission. Before each RF transmission from the transmitter 102 takesplace, both the transmitter 102 and the receiver 104 is configured torecognize in which one of the 320 time segments the data transmissionwill occur (or in which to start, if the transmission time exceeds 25milliseconds). Accordingly, receiver 104 only listens for a RFtransmission in a single 25 millisecond time segment each minute, whichvaries from minute to minute within the 10 second time window.

Moreover, each transmitter 102 is configured to maintain a “master time”clock that the associated receiver unit 104 may reference to each minute(based on the time of transmission and known offset for that minute.). Acounter also on the transmitter 102 may be configured to keep track of avalue for transmit time (TxTime) that increments by 1 each minute, from0 to 255 and then repeats. This transmit time (TxTime) value istransmitted in the data packet each minute, shown as Byte 0 in FIG. 4.Using the transmit time (TxTime) value and the transmitter's uniqueidentification information, both the transmitter 102 and the receiver104 may be configured to calculate which of the 320 time segments willbe used for the subsequent transmission. In one embodiment, the functionthat is used to calculate the offset from the master clock 1-minute tickis a pseudo-random number generator that uses both the transmit window(TxTime) and the transmitter identification information (TxID) as seednumbers. Accordingly, the transmission time varies pseudo-randomlywithin the 10 second window for 256 minutes, and then repeats the sametime hopping sequence again for that particular transmitter 102.

In the manner described above, in accordance with one embodiment of thepresent invention, co-location collisions may be avoided with theabove-described time hopping procedure. That is, in the event that twotransmitters interfere with one another during a particulartransmission, they are not likely to fall within the same time segmentin the following minute. As previously described, three glucose datepoints are transmitted each minute (one current and tworedundant/historical), so collisions or other interference must occurfor 3 consecutive data transmissions for data to be lost. In one aspect,when a transmission is missed, the receiver 104 may be configured tosuccessively widen its listening window until normal transmissions fromthe respective transmitter 102 resume. Under this approach, thetransmitter listens for up to 70 seconds when first synchronizing with atransmitter 102 so it is assured of receiving a transmission fromtransmitter 102 under normal conditions.

In the manner described above, in accordance with the embodiments of thepresent invention, there is provided a continuous glucose monitoring andmanagement system in accordance with one embodiment of the presentinvention including a sensor configured to detect one or more glucoselevels, a transmitter operatively coupled to the sensor, the transmitterconfigured to receive the detected one or more glucose levels, thetransmitter further configured to transmit signals corresponding to thedetected one or more glucose levels, a receiver operatively coupled tothe transmitter configured to receive transmitted signals correspondingto the detected one or more glucose levels, where the transmitter isconfigured to transmit a current data point and at least one previousdata point, the current data point and the at least one previous datapoint corresponding to the detected one or more glucose levels.

The receiver may be operatively coupled to the transmitter via an RFcommunication link, and further, configured to decode the encodedsignals received from the transmitter.

In one embodiment, the transmitter may be configured to periodicallytransmit a detected and processed glucose level from the sensor to thereceiver via the RF data communication link. In one embodiment, thetransmitter may be configured to sample four times every second toobtain 240 data points for each minute, and to transmit at a rate of onedata point (e.g., an average value of the 240 sampled data points forthe minute) per minute to the receiver.

The transmitter may be alternately configured to transmit three datapoints per minute to the receiver, the first data point representing thecurrent sampled data, and the remaining two transmitted data pointsrepresenting the immediately past two data points previously sent to thereceiver. In this manner, in the case where the receiver does notsuccessfully receive the sampled data from the transmitter, at thesubsequent data transmission, the immediately prior transmitted data isreceived by the receiver. Thus, even with a faulty connection betweenthe transmitter and the receiver, or a failed RF data link, the presentapproach ensures that missed data points may be ascertained from thesubsequent data point transmissions without retransmission of the misseddata points to the receiver.

The transmitter may be configured to encode the detected one or moreglucose levels received from the sensor to generate encoded signals, andto transmit the encoded signals to the receiver. In one embodiment, thetransmitter may be configured to transmit the encoded signals to thereceiver at a transmission rate of one data point per minute. Further,the transmitter may be configured to transmit the current data point andthe at least one previous data point in a single transmission per minuteto the receiver. In one aspect, the current data point may correspond toa current glucose level, and where the at least one previous data pointmay include at least two previous data points corresponding respectivelyto at least two consecutive glucose levels, the one of the at least twoconsecutive glucose levels immediately preceding the current glucoselevel.

In a further embodiment, the receiver may include an output unit foroutputting the received transmitted signals corresponding to one or moreglucose levels. The output unit may include a display unit fordisplaying data corresponding to the one or more glucose levels, wherethe display unit may include one of a LCD display, a cathode ray tubedisplay, and a plasma display.

The displayed data may include one or more of an alphanumericrepresentation corresponding to the one or more glucose levels, agraphical representation of the one or more glucose levels, and athree-dimensional representation of the one or more glucose levels.Moreover, the display unit may be configured to display the datacorresponding to the one or more glucose levels substantially in realtime.

Further, the output unit may include a speaker for outputting an audiosignal corresponding to the one or more glucose levels.

In yet a further embodiment, the receiver may be configured to store anidentification information corresponding to the transmitter.

The receiver may be further configured to perform a time hoppingprocedure for synchronizing with the transmitter. Alternatively, thereceiver may be configured to synchronize with the transmitter based onthe signal strength detected from the transmitter, where the detectedsignal strength exceeds a preset threshold level.

The transmitter in one embodiment may be encased in a substantiallywater-tight housing to ensure continuous operation even in the situationwhere the transmitter is in contact with water.

Furthermore, the transmitter may be configured with a disable switchwhich allows the user to temporarily disable the transmission of data tothe receiver when the user is required to disable electronic devices,for example, when aboard an airplane. In another embodiment, thetransmitter may be configured to operate in an additional third state(such as under Class B radiated emissions standard) in addition to theoperational state and the disable state discussed above, so as to allowlimited operation while aboard an airplane yet still complying with theFederal Aviation Administration (FAA) regulations. Additionally, thedisable switch may also be configured to switch the transmitter betweenvarious operating modes such as fully functional transmission mode,post-manufacture sleep mode, and so on. In this manner, the power supplyfor the transmitter is optimized for prolonged usage by effectivelymanaging the power usage.

Furthermore, the transmitter may be configured to transmit the data tothe receiver in predetermined data packets, encoded, in one embodiment,using Reed Solomon encoding, and transmitted via the RF communicationlink. Additionally, in a further aspect of the present invention, the RFcommunication link between the transmitter and the receiver of thecontinuous glucose monitoring system may be implemented using a lowcost, off the shelf remote keyless entry (RKE) chip set.

The receiver in an additional embodiment may be configured to perform,among others, data decoding, error detection and correction (using, forexample, forward error correction) on the encoded data packets receivedfrom the transmitter to minimize transmission errors such as transmitterstabilization errors and preamble bit errors resulting from noise. Thereceiver is further configured to perform a synchronized time hoppingprocedure with the transmitter to identify and synchronize with thecorresponding transmitter for data transmission.

Additionally, the receiver may include a graphical user interface (GUI)for displaying the data received from the transmitter for the user. TheGUI may include a liquid crystal display (LCD) with backlighting featureto enable visual display in dark surroundings. The receiver may alsoinclude an output unit for generating and outputting audible signalalerts for the user, or placing the receiver in a vibration mode foralerting the user by vibrating the receiver.

More specifically, in a further aspect, the receiver may be configuredto, among others, display the received glucose levels on a displaysection of the receiver either real time or in response to user request,and provide visual (and/or auditory) notification to the user of thedetected glucose levels being monitored. To this end, the receiver isconfigured to identify the corresponding transmitter from which it is toreceive data via the RF data link, by initially storing theidentification information of the transmitter, and performing a timehopping procedure to isolate the data transmission from the transmittercorresponding to the identification information and thus to synchronizewith the transmitter. Alternatively, the receiver may be configured toidentify the corresponding transmitter based on the signal strengthdetected from the transmitter, determined to exceed a preset thresholdlevel.

A method in accordance with one embodiment of the present inventionincludes the steps of receiving an identification informationcorresponding to a transmitter, detecting data within a predetermined RFtransmission range, determining whether the detected data is transmittedfrom the transmitter, decoding the detected data, and generating anoutput signal corresponding to the decoded data.

In one embodiment, the step of determining whether the detected datatransmission is transmitted from the transmitter may be based on thereceived identification information. In another embodiment, the step ofdetermining whether the detected data transmission is transmitted fromthe transmitter may be based on the signal strength and duration of thedetected data within the predetermined RF transmission range.

In a further embodiment, the step of decoding may also include the stepof performing error correction on the decoded data. Moreover, the stepof decoding may include the step of performing Reed-Solomon decoding onthe detected data.

Additionally, in yet a further embodiment of the present invention,transmitter identification information may not be included in thetransmitted data from the transmitter to the receiver. Rather, thereceiver may be configured to determine the transmitter identificationinformation from the received data by using Reed Solomon decoding. Morespecifically, when decoding the first data packet received from atransmitter, the receiver may be configured to set the valuecorresponding to the transmitter identification information to zero, andto indicate to the Reed Solomon decoder that the transmitteridentification information is known to be incorrect. The Reed Solomondecoder may then be configured to use this information to moreeffectively “correct” during the error correction procedure, andtherefore to recover the transmitter identification information from thereceived data. Indeed, in subsequent data packets, the received pads andthe received data packet with the known transmitter identificationinformation are used to facilitate with the error detection.

In the manner described, the present invention provides a continuousglucose monitoring system that is simple to use and substantiallycompact so as to minimize any interference with the user's dailyactivities. Furthermore, the continuous glucose monitoring system may beconfigured to be substantially water-resistant so that the user mayfreely bathe, swim, or enjoy other water related activities while usingthe monitoring system. Moreover, the components comprising themonitoring system including the transmitter and the receiver areconfigured to operate in various modes to enable power savings, and thusenhancing post-manufacture shelf life.

Various other modifications and alterations in the structure and methodof operation of this invention will be apparent to those skilled in theart without departing from the scope and spirit of the invention.Although the invention has been described in connection with specificpreferred embodiments, it should be understood that the invention asclaimed should not be unduly limited to such specific embodiments. It isintended that the following claims define the scope of the presentinvention and that structures and methods within the scope of theseclaims and their equivalents be covered thereby.

What is claimed is:
 1. A data monitoring and management system,comprising: a communication link; a transmitter operatively coupled tothe communication link, the transmitter configured to transmit a firstdata packet during a transmit time window selected from a plurality oftransmission windows, the selected transmit time window determined basedon transmitter identification information and a transmit time value,wherein the transmitter identification information is used as a seednumber to determine a transmission time for subsequent data packets thatare randomly varied within a predetermined time window; and a receiveroperatively coupled to the communication link, wherein the receiverreceives the transmitted first data packet during a data reception timeperiod synchronized with the transmit time window based on a phaselocked start indicator, wherein the transmitted first data packet doesnot include the transmitter identification information, and furtherwherein the receiver receives one or more further data packets from thetransmitter when the transmitter identification information is verifiedbased on the received first data packet; wherein the receiver processesthe received first data packet and the one or more further data packetswhen the transmitter identification information and the transmit timevalue of each data packet transmission is verified.
 2. The system ofclaim 1, wherein the communication link includes an RF communicationlink.
 3. The system of claim 1, wherein the transmitter is configured totransmit a data packet at each predetermined time interval.
 4. Thesystem of claim 3, wherein the predetermined time interval is oneminute.
 5. The system of claim 1, wherein the receiver performs errorcorrection on a received data packet.
 6. The system of claim 1, furtherincluding a sensor to detect one or more glucose levels, wherein thesensor is in signal communication with the transmitter.
 7. The system ofclaim 6, wherein the sensor is disposed in physical contact with thetransmitter.
 8. The system of claim 6, wherein the transmitter convertsa sensor signal received from the sensor into a corresponding data fortransmission to the receiver.
 9. The system of claim 6, furtherincluding a medication delivery unit operatively coupled to thereceiver, the medication delivery unit determines a medicationadministration protocol based on signals received from the receiver. 10.The system of claim 9, wherein the medication delivery unit includes aninsulin pump, and further wherein the medication administration protocolincludes one or more of a bolus calculation, and a basal profilemodification.
 11. The system of claim 9, wherein the receiver determinesa glucose level corresponding to the sensor signal, and further, whereinthe receiver outputs glucose level information.
 12. The system of claim9, wherein the medication delivery unit wirelessly communicates with thereceiver.
 13. A continuous glucose monitoring and management system,comprising: an RF communication link; a transmitter operatively coupledto the RF communication link, wherein the transmitter periodicallytransmits a data packet at each predetermined time interval; and areceiver operatively coupled to the RF communication link, wherein thereceiver receives a first transmitted data packet during a datareception time window synchronized with a transmit time window of thetransmitter based on a phase locked start indicator, the transmit timewindow selected from a plurality of transmission windows, the selectedtransmit time window determined based on transmitter identificationinformation and a transmit time value, wherein the first transmitteddata packet does not include the transmitter identification information,wherein the transmitter identification information is used as a seednumber to determine a transmission time for subsequent data packets thatare randomly varied within a predetermined time window, and further,wherein the receiver receives one or more subsequent data packets fromthe transmitter when the transmitter identification information isverified based on the received first transmitted data packet; whereinthe receiver processes the received first transmitted data packet andthe one or more subsequent data packets when the transmitteridentification information and the transmit time value of each datapacket transmission is verified.
 14. The system of claim 13, wherein adata packet received from the transmitter correspond to a respectivemeasured glucose level of a patient.
 15. The system of claim 14, furtherincluding an insulin pump operatively coupled to the receiver, whereinthe insulin pump determines an insulin administration protocol based onsignals received from the receiver.
 16. The system of claim 15, whereinthe insulin administration protocol includes one or more of a bolusdetermination, and a basal rate modification determination.
 17. Thesystem of claim 15, wherein the insulin pump is disposable.
 18. Thesystem of claim 13, wherein the predetermined time interval fortransmitter data packet transmission includes one transmission perminute.
 19. A method of providing continuous glucose monitoring andmanagement, comprising the steps of: providing an RF communication link;periodically transmitting a data packet at each predetermined timeinterval during a transmit time window selected from a plurality oftransmission windows, the selected transmit time window determined basedon transmitter identification information and a transmit time value,over the RF communication link, wherein the transmitter identificationinformation is used as a seed number to determine transmission time forsubsequent data packets that are randomly varied within a predeterminedtime window; receiving a first transmitted data packet over the RFcommunication link during a data reception time period synchronized withthe selected transmit time window based on a phase locked startindicator, wherein the first transmitted data packet does not includethe transmitter identification information; receiving one or moresubsequent data packets over the RF communication link when thetransmitter identification information is verified from the firsttransmitted data packet based on the received first transmitted datapacket; and processing the received first transmitted data packet andthe one or more subsequent data packets when the transmitteridentification information and the transmit time value of each datapacket transmission is verified.
 20. The method of claim 19, wherein thepredetermined time interval is approximately one minute.
 21. The methodof claim 19, including performing error detection on one or more of thefirst transmitted data packet or the one or more subsequent datapackets.
 22. The method of claim 21, including performing errorcorrection on the one or more of the first transmitted data packet orthe one or more subsequent data packets when an error is detected. 23.The method of claim 22, wherein performing the error correction includesexecuting forward error correction.
 24. The method of claim 19,including performing Reed Solomon coding.